play framework personal notes

Initial setting

** application.conf file **

//Add the following to db(Initially it is h2, so rewrite it)
  default.driver = org.postgresql.Driver
  default.url = "jdbc:postgresql://localhost:5433/projectName"
  default.username = postgres
  default.password = postgres

//Add below to the last line
ebean.default="models.*"

plugins.sbt

//Add the following to the last line
addSbtPlugin("com.typesafe.sbteclipse" % "sbteclipse-plugin" % "4.0.0")

//Also, since the following is initially set as a comment, delete the comment
addSbtPlugin("com.typesafe.sbt" % "sbt-play-ebean" % "3.0.2")

build.sbt

lazy val root = (project in file(".")).enablePlugins(PlayJava)To
lazy val root = (project in file(".")).enablePlugins(PlayJava, PlayEbean)To

//Add the following to the last line
libraryDependencies += "org.postgresql" % "postgresql" % "42.0.0.jre7"
EclipseKeys.preTasks := Seq(compile in Compile)
EclipseKeys.projectFlavor := EclipseProjectFlavor.Java
EclipseKeys.createSrc := EclipseCreateSrc.ValueSet(EclipseCreateSrc.ManagedClasses, EclipseCreateSrc.ManagedResources)

cache

Controller.java

//DI
@Inject
private CacheApi cache;

//Set cache (can set non-string objects)
cache.set("key", item);
//Set the cache with an expiration date of only 15 minutes
cache.set("key", item, 60 * 15);
//Get cache
Item item = (Item) cache.get("key");
//Delete cache
cache.remove("key");

session Note that only String can be entered

Controller.java

//Set the value in session
session("email", "[email protected]");
//Get the value set in session
String user = session("email");
//Clear the value of session
session().remove("email");

index.html

<!--How to retrieve values in html-->
@session.get("email");

<!--Embedded in hidden-->
<input type="hidden" value="@session.get("id")" id = "idInHidden">

rendering

return ok(views.html.(html file name).render();

redirect

return redirect("/item/");

** Validation **

RegisterForm.java

@Required(message = "Enter your email")
private String email;

index.html

@if(form.error("email") != null) {
      <span style="color: red">
        @form.error("email").message()
       </span>
}

finder When using finder, add the following to the model class

Item.java

package models;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;

@Entity
@Table(name = "items")
public class Item extends Model {
  @Id
  @GeneratedValue(strategy = GenerationType.AUTO)
  private Integer id;
  private String name;
  private String brand;
  private Integer category;
  private double price;

  public static Finder<Integer, Item> finder = new Finder<Integer, Item>(Integer.class, Item.class);

  //Getter below, setter
}

ItemService.java

public List<Item> getBrandByGrandChildId(String grandChildId){
  Integer id = Integer.parseInt(grandChildId);
  List<Item> brandList = Item.finder.select("brand").where().eq("category", id).ne("brand", null).setDistinct(true).findList();
  return brandList;

//eq(field,value);    「field =value」のレコードを検索する
//ne(field,value);    「field !=value」のレコードを検索する
//lt(field,value);    「field <value」のレコードを検索する
//gt(field,value);    「field >value」のレコードを検索する
//le(field,value);    「field <=value」のレコードを検索する
//ge(field,value);    「field>=value」のレコードを検索する
//ilike(field,value); 「field likevalue」のレコードを検索する
}

** Raw SQL **

itemService.java

public Item findById(Integer id) {
  String sql = "select * from items where a.id = ?";
  SqlRow sqlRow = Ebean.createSqlQuery(sql).setParameter(1, id).findUnique();
  return sqlRow
}